SENVILLE R454B Central Heat Pump | 3 Tons - 36000 BTU

A 3-ton central heat pump designed to replace the old system without sacrificing comfort during Quebec's cold spells

When a homeowner already has a duct network, replacing an old central air conditioner or an aging heat pump must be evaluated differently from a wall-mounted project. The question is not simply whether to choose “3 tons because the old unit was 3 tons.” The heat load, available airflow, duct dimensions, electrical capacity, low-temperature heating requirements, and compatibility with the existing installation must all be verified.

The 3-ton, 36,000 BTU SENVILLE SENDC-36HF R454B central heat pump is designed precisely for this type of project. The manufacturer's documentation identifies the system as the SENDC-36HF, a 36,000 BTU central air conditioning and heat pump system.

At AirGreen Heat Pumps, Air Conditioning & Heating, we view this model as a particularly relevant solution for certain homes in Montreal, Laval, Longueuil, the South Shore, the North Shore, and Montérégie where a duct network is already present and the owner wants to switch to a more modern inverter technology operating with R-454B.

The combination listed on our AirGreen product sheet is:

• Outdoor unit: SENDC-36HF-OG
• Indoor unit: SENDC-36HF-IG
• Nominal capacity: 3 tons / 36,000 BTU
• AHRI: 215735328
• ENERGY STAR®: yes
• ENERGY STAR® Cold Climate: yes
• ENERGY STAR ID: 3649597
• Refrigerant: R-454B
• SEER2: 17.4
• EER2: 11.7
• HSPF2-4: 10.3
• Heating down to -30 °C
• WiFi: optional
• Voltage: 220 V
• Piping: 3/8 in – 3/4 in
• MCA: 41 A
• MOP: 50 A
• Maximum indoor airflow: 1,188 CFM

3 tons means 36,000 BTU, but the inverter completely changes how that capacity is used

One ton of cooling corresponds to approximately 12,000 BTU/h. A 3-ton unit therefore corresponds to a nominal capacity of approximately 36,000 BTU/h.

With an inverter heat pump, however, this value is not a fixed capacity.

The Senville brochure indicates a cooling range from 13,000 to 47,400 BTU/h and a heating range from 11,000 to 57,200 BTU/h.

This modulation is particularly useful in a central system.

At the beginning of a hot summer day, demand may be high. As the indoor temperature then approaches the setpoint, the compressor can reduce its speed instead of operating only in on-off cycles.

In heating mode, the principle is similar. A November day a few degrees above freezing does not impose the same load as a January night at -20 °C. The inverter allows the system to adjust its output more closely to the actual load.

This is something we examine carefully when replacing a central heat pump in Montreal or Laval, because the comfort provided by a central system depends greatly on the unit's ability to maintain a stable temperature without unnecessarily increasing the number of start-ups.

Up to 1,400 sq. ft. according to Senville: why we never size a system based on square footage alone

Senville presents this 36,000 BTU unit as suitable for spaces of up to approximately 1,400 sq. ft., for residential or commercial applications.

This indication is useful for positioning the product, but it should never replace a load calculation.

We regularly see two homes of comparable size with very different requirements. A well-insulated property in Boucherville with newer windows may require much less energy than an older building of the same size in Montreal, even if both have a central system.

We must consider factors including insulation, air infiltration, windows, ceiling height, solar exposure, number of floors, basement heat loss, and ductwork configuration.

The presence of an old 36,000 BTU unit is not proof that 36,000 BTU is still the right capacity. Renovations, window replacements, or improved insulation may have changed the building's requirements.

The performance at -8 °C, -15 °C, and -30 °C is more informative than the statement “operates at -30 °C”

The AirGreen data sheet provides three particularly interesting figures for our climate.

At -8 °C, the listed capacity is 31,800 BTU/h, with a COP of approximately 2.56.

At -15 °C, the listed capacity reaches 39,000 BTU/h, with a COP of approximately 1.9.

At -30 °C, the listed maximum capacity is still 27,800 BTU/h, with a COP of approximately 1.59.

The manufacturer's documentation confirms that the system is designed to provide heating down to -22 °F, or -30 °C.

These figures illustrate an important distinction we often explain to homeowners: a heat pump that can operate at -30 °C does not necessarily retain its maximum capacity or its best efficiency at -30 °C.

For this Senville unit, a maximum capacity of 27,800 BTU at -30 °C remains significant for a central heat pump in this category, but it must be compared with the home's actual heat loss.

If the property requires, for example, more heat than the heat pump can provide during an extreme cold spell, auxiliary heating will need to take over or operate in conjunction with it.

Auxiliary heating: an element to plan from the quotation stage

Senville documentation shows that the system can be configured with 10 kW, 15 kW, or 20 kW auxiliary heating elements.

This detail is particularly relevant in Quebec.

Auxiliary electric heating should not be selected arbitrarily. Its capacity must match the building’s needs and the available electrical capacity.

In a home where the central heat pump replaces an old electric furnace, we therefore check all of the following simultaneously:

the heat pump’s capacity, the existing or planned supplemental heating, the electrical panel, available capacity, and the operating strategy during periods of extreme cold.

Systematically installing the largest available component is not always the best decision. A larger component also requires greater electrical capacity.

SEER2 17.4, EER2 11.7, and HSPF2-4 10.3

The official technical documentation lists a SEER2 of 17.4, an EER2 of 11.7, an HSPF2-4 of 10.3, and a nominal COP of 3.36.

In some sales materials, we still see only the terms “SEER,” “EER,” or “HSPF.” For this combination, the brochure correctly uses the ratings SEER2, EER2, and HSPF2, which correspond to current testing methods.

For homeowners, these values are mainly useful for comparing central systems in the same category.

An attractive SEER2 rating helps reduce the amount of electricity required for cooling during the summer season. HSPF2 is more representative of seasonal heating efficiency.

In the Greater Montreal climate, heating obviously plays a major role in the economic analysis of a central heat pump.

1,188 CFM: why the ductwork must be checked before installation

The indoor unit offers three airflow levels:

1,188 CFM at high speed, 1,082 CFM at medium speed, and 970 CFM at low speed.

These data are essential in a central-system project.

A heat pump can deliver excellent performance on paper yet produce disappointing results if the ductwork is too restrictive, poorly balanced, or partially obstructed.

In our assessments at AirGreen, we pay attention to symptoms that may reveal a distribution problem:

bedrooms receiving almost no air, an overly restrictive return grille, crushed ducts, one floor heating much less than the other, or excessive blowing noise at certain outlets.

Replacing the equipment does not automatically correct these deficiencies.

To properly handle an airflow of up to 1,188 CFM, we must ensure that the existing installation allows the indoor unit to circulate air properly.

A 49-inch-high central indoor unit

The indoor unit measures approximately:

21.02 in wide × 21.02 in deep × 49.02 in high

and weighs approximately 129.19 lb.

The outdoor unit measures:

38.58 in × 16.34 in × 38.39 in

with a stated weight of 227 lb.

These dimensions must be verified before ordering the equipment.

In some mechanical rooms in older Montreal homes, the space between the wall, water heater, pipes, and ventilation system may be limited. Replacing an old furnace with a different indoor unit may require sheet-metal transitions, a plenum modification, or an adjustment to the return air.

At AirGreen, we prefer to assess these constraints before installation rather than treat them as a surprise on the morning of the work.

Indoor sound level: 41 to 45 dB(A)

The stated sound level of the indoor unit is:

41 dB(A) at low speed, 43 dB(A) at medium speed, and 45 dB(A) at high speed.

For a central system, these figures must be interpreted together with the duct system.

The noise perceived in the rooms depends as much on the unit’s operation as on the duct diameter, grilles, air speed, and proximity to the mechanical room.

An undersized duct system can produce more turbulence and noise, even when the equipment itself is operating normally.

64 dB(A) for the outdoor unit: location matters

The outdoor unit is rated at 64 dB(A) and can move up to 4,500 CFM of air.

This detail deserves particular attention in neighborhoods where properties are close together.

The outdoor unit should not be installed solely where the refrigerant line route is easiest. We must also consider bedrooms, windows, neighbors, property lines, and applicable municipal regulations.

The Senville brochure also contains a verified buyer review reporting an annoying whistling sound coming from the outdoor unit, to the point that the neighbors complained about it. The total sample consists of only three reviews, and this comment does not establish that the model has a widespread problem, but it does serve as a reminder that the actual noise produced by an installation deserves to be taken seriously.

In the field, when an unusual noise appears after an installation, we do not automatically consider the sound level “normal.” An inspection may be necessary to distinguish normal aerodynamic noise from hissing, vibration, support resonance, or a problem requiring diagnosis.

SENVILLE SENDC-36HF installation: the technical details that determine long-term performance

208/230 V power supply, 41 A MCA, and 50 A maximum protection

Senville documentation indicates a power supply:

208/230 V, single-phase, 60 Hz

with an operating range of 187 to 253 V. The MCA is 41 A, and the indicated maximum fuse or circuit breaker is 50 A.

This is not a heat pump that can simply be added to an electrical panel without verification.

During a central heat pump installation in Laval, Montreal, or Longueuil, we must check the panel’s available capacity and consider the installation as a whole, especially when electric auxiliary heating is added.

A 10, 15, or 20 kW heating element represents a significant additional electrical load.

R-454B: 165.79 oz and precharge for 25 feet

The brochure indicates an R-454B charge of 165.79 oz with a precharge intended for 25 feet of piping.

The AirGreen specification sheet indicates piping of 3/8 in – 3/4 in.

During a replacement, we must therefore inspect the existing piping very carefully.

The fact that a house already has two copper lines between the mechanical room and the outdoor unit does not mean they are automatically suitable for the new system.

We check their diameter, length, condition, accessibility, and compatibility with the requirements of the new equipment.

This is one of the points that can make a major difference in the cost and quality of a central heat pump replacement.

Wall-mounted thermostat and optional WiFi

The brochure specifies that the control type is a wall-mounted control.

The AirGreen specification sheet indicates that WiFi is available as an option.

This detail must be clarified when preparing the quote if the owner absolutely wants to control the heat pump with their phone.

In a central system, the choice of thermostat is also more important than it may seem. An inverter heat pump uses specific control logic, and we must ensure that the thermostat or control provided allows the system to operate as designed.

Advertised provincial rebate: $3,816

The AirGreen product sheet indicates a $3,816 provincial rebate for this combination, associated in particular with:

SENDC-36HF-OG + SENDC-36HF-IG

AHRI 215735328

ENERGY STAR® 3649597

Cold Climate: yes

For a homeowner comparing the price of a central heat pump with that of a basic central air conditioner, this financial assistance can significantly change the project's economics.

However, we always recommend confirming the eligibility criteria and available amount at the time of quoting, since a rebate program may be changed.

The exact AHRI identification is particularly important: two commercially similar 36,000 BTU systems are not necessarily associated with the same certificate or the same amount.

A warranty that deserves verification before publication

The AirGreen product sheet provided indicates a warranty of:

10 years compressor – 10 years parts – 0 years labour

with the possibility of additional warranty coverage.

However, the attached manufacturer's brochure states 10 years on the compressor and 5 years on parts.

Senville also mentions this 10-year compressor and 5-year parts coverage in the product description.

This difference must be confirmed before presenting the final warranty to the customer. There may be a specific warranty program associated with the distributor, registration, or AirGreen sales channel, but the brochure provided is not sufficient to confirm the 10-year parts coverage shown on the product sheet.

For us, this transparency is important: the warranty that actually applies must be clearly shown on the quote.

A typical replacement scenario we encounter

A representative project is a home equipped with an older central system that still provides cooling, but whose compressor is beginning to show signs of wear.

The homeowner is hesitating between reinstalling a basic central air conditioner and converting the system to a Cold Climate central heat pump.

With the SENDC-36HF, several factors must therefore be verified before even discussing installation:

Can the old system properly handle approximately 1,188 CFM? Can the electrical panel accommodate the outdoor unit and auxiliary heating? Are the existing refrigerant lines compatible? Does the mechanical room provide the required 49 inches of clearance? Do the home's heat losses allow the heat pump to cover a significant portion of the heating load even when the temperature drops below -15 °C?

These are the questions that distinguish a simple equipment replacement from a properly planned HVAC installation.

The mistakes we strive to avoid

Automatically replacing an old 3-ton unit with a new 3-ton unit

The previous capacity is useful information, but it does not replace verifying the building’s current heating load.

Ignoring the ductwork system

A high-performance central unit cannot compensate for a ductwork system that does not distribute air properly.

Looking only at the minimum temperature of -30 °C

The actual capacity at -30 °C is much more relevant. In this configuration, the AirGreen specifications indicate a maximum of 27,800 BTU/h at -30 °C.

Neglecting auxiliary heating

The choice between 10, 15, or 20 kW must be incorporated into the building’s electrical and thermal analysis.

Reusing the refrigerant lines without validation

The 3/8 in – 3/4 in diameter, length, and condition of the copper lines must meet the needs of the new unit.

Installing the outdoor unit near a bedroom or neighbour solely to shorten the lines

With a stated sound level of 64 dB(A), the location deserves serious consideration.

Why choose AirGreen for a 3-ton SENVILLE central heat pump

At AirGreen Heat Pumps, Air Conditioning & Heating, we approach a central installation as a complete system: the heat pump, indoor unit, ductwork, electrical system, thermostat, drainage, refrigerant lines, and supplemental heating must all work together.

For a project involving the SENVILLE SENDC-36HF R454B 36,000 BTU, we can verify sizing, airflow through the existing ductwork, the condition of the ducts, the electrical panel, auxiliary heating, the 3/8 in – 3/4 in refrigerant line routing, the outdoor unit location, and eligibility for financial assistance programs.

This approach is relevant both for replacing a system in a Laval bungalow and for a major renovation in Montreal, a home in Longueuil, a property on the South Shore, or a project on the North Shore.

The SENVILLE SENDC-36HF has features that are well suited to Quebec: inverter technology, 36,000 nominal BTU, heating down to -30 °C, a stated maximum capacity of 27,800 BTU at that temperature, SEER2 of 17.4, Cold Climate certification, and R-454B refrigerant. However, the quality of the result will depend directly on proper sizing and integration with the building.

Contact AirGreen for a quote on the 3-ton SENVILLE SENDC-36HF R454B central heat pump, to check compatibility with your ductwork and plan a complete HVAC installation in Montreal, Laval, Longueuil, the South Shore, or the North Shore.